Daily Archives: September 10, 2017

Mooring madness on the Sally Ride

The R/V Sally Ride arrived on site Friday morning local time and got right to work.  We had initially laid out what we thought was a slightly conservative but reasonable schedule of mooring deployments that would last for the first 4.5 days of our expedition.  We had not counted on the incredible energy, talent, precision and hard work of all of our mooring teams.  Friday we deployed 13 moorings, including the two large NRL ‘quad-pods’, and today another 17!  After two days of hard work we now have all but the final 5 deployed. Instead of being done mid-day on Tuesday, we now expect to have completed all mooring deployments by mid-day Sunday.  This will allow us to switch to process-based survey mode full time, joining our colleagues on the Oceanus, Sproul, Kalipi, and Sounder in coordinated sampling. We’ve been practicing our survey techniques on the night watch; more on some of those preliminary results tomorrow.  In the meantime, a few photos of our team hard at work.

On board the Kalipi (9/9/17)

Today we deployed OC10N-T and OC10N-A, the last of the moorings deployed by the Oceanus/Kalipi group.  We then rigged the Kalipi for survey mode (side-mounted ADCP and fast profiling CTD).  Will commence surveys tomorrow (9/10) in coordination with the Oceanus.

On board the Kalipi:  Una, Matt, Taylor and Jenny.

Getting ready to deploy OC10N-T:  Jim and Matt.

View of Sally Ride and Oceanus (in the distance) from the Kalipi.

Drifter Test Day

Sep 9, 2017

Today we (SIO and APL crews) tested out releasing and recovering drifters. We released 3 clusters of 9 drifters off the Pismo Beach Pier (see Figs below). All drifters were released by approximately 11:00 and drifted for about 3 hrs. The drifters displaced approximately 3 km in these 3 hours, so the surface current magnitude is |u|~25 cm/s. After deployment, ADCP transects were performed (and numerous whales were spotted). It was a pleasant day and everything went as anticipated. We look forward to the NPS crew joining the fun.

Matt

Drifter test day, zoomed out angle. Initial release locations are black dots.

Drifter test day tracks, zoomed in. Initial release locations are black dots.

 

The R/V Sounder made 4 transects running east-west through the drifter clusters, each time observing a similar velocity structure.  By coincidence, the drifter release points bracketed a current constrained laterally within the array and vertically to 10 m depth.  Very cool feature.

Four transects through the drifter array.

The Nortek Signature profiles collected from the SWIFT drifters are consistent with the center of this velocity signal.

SWIFT relative velocity profiles.

Chasing an internal bore on Oceanus

A few images from today’s exploration on R/V Oceanus. It was great to see the Oceano array complete with the final installation by the R/V Sally Ride at OC25NB and by the R/V Kalipi at OC10N. It’s satisfying to see our paper plans become reality.

—Jack Barth and the OSU team onboard R/V Oceanus

We chased an internal bore from offshore to the 20-m isobath. We made repeated transects through the bore and saw it evolve as it propagated shoreward. The front had a nice convergence line of foam and we saw diving seabirds in the acoustics and with our eyes as they lined up to take advantage of the accumulation of food. Mick’s radar showed it nicely and it did keep propagating shoreward in to waters shallower than Oceanus can sample. Jim Lerczak and Kalipi will have fun sampling that region.

scripps oceanography uc san diego